In recent years, a flexible printed board is used in various electronic devices. For example, this is especially a necessary electronic component in case of a folding type cellular phone in which an operation section and a display section are connected through a hinge section, in order to connect the operation section and the display section. More specifically, in a folding type cellular phone, an interconnection board section which is formed to be bendable to pass through the hinge section, is arranged, and terminal board sections formed at both ends are connected to other boards and parts mounted within each housing.
Here, one example of a flexible printed board used for a folding cellular phone is disclosed in Japanese Patent Application Publication (JP-P2004-247653A). A flexible printed board disclosed in this citation employs a structure that the flexible printed board to which an interconnection board section with symmetric bilateral shapes and terminal board sections are formed, is folded for stacking such that a singe layer in which interconnections are formed, is sufficient even when the terminal board sections are formed at both ends.